The changes were announced Thursday as part of a broader plan to bolster the nation’s arsenal of tools in its fight against the virus as the world enters its third year of the pandemic.
The plan is also the latest move by the Biden Administration to lessen the spread of the new, highly mutated Omicron variant of the coronavirus, which was first reported to the WHO by South Africa a week ago. At least 23 countries have identified Omicron cases thus far, and that number is expected to rise in the coming days and weeks, the WHO said Wednesday.
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A senior Administration official confirmed to Fox News Thursday that the 24-hour testing requirement, which Biden officially announced earlier in the day, will go into effect on Monday. Regardless of vaccination or citizenship status, all travelers will be subject to the changed regulation.
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Previously, only the unvaccinated were required to show a negative test 24 hours prior to departure, while those who were vaccinated were ordered to show a negative test within 72 hours.
The changes come as part of Biden's winter plan to combat COVID-19 as cases of the Omicron variant began to spring up around the U.S. this week.
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"Experts say that COVID-19 cases will continue to rise in the weeks ahead this winter, and that we will see more omicron cases here in the United States in the days, weeks and months ahead. Our best scientists and doctors are on the case and gathering data, but early indications are that our vaccines will provide a measure of protection against this strain," Biden said in an op-ed published in USA Today Thursday.
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Biden also announced a campaign to continue encouraging Americans to get vaccinated or get booster shots if they have previously received the jab, expanding access to vaccines with more walk-in appointments and longer hours and weekend availability at vaccination sites.
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The plan also calls for insurers to pay 100% of the cost of in-home testing kits, and they will be provided for free pickup for those who do not have private insurance.
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"We are going to fight COVID-19 not with shutdowns or lockdowns – but with more widespread vaccinations, boosters, testing and more," Biden declared. "We will beat it back with science and speed, not chaos and confusion – just as we did in the spring and again with the more powerful delta variant in the summer and fall."